[maven-release-plugin] prepare release maven-compiler-plugin-3.9.0

pom.xml

@@ -26,11 +26,11 @@ under the License.
     <groupId>org.apache.maven.plugins</groupId>
     <artifactId>maven-plugins</artifactId>
     <version>34</version>
-    <relativePath/>
+    <relativePath />
   </parent>
 
   <artifactId>maven-compiler-plugin</artifactId>
-  <version>3.9.0-SNAPSHOT</version>
+  <version>3.9.0</version>
   <packaging>maven-plugin</packaging>
 
   <name>Apache Maven Compiler Plugin</name>
@@ -45,7 +45,7 @@ under the License.
     <connection>scm:git:https://gitbox.apache.org/repos/asf/maven-compiler-plugin.git</connection>
     <developerConnection>scm:git:https://gitbox.apache.org/repos/asf/maven-compiler-plugin.git</developerConnection>
     <url>https://github.com/apache/maven-compiler-plugin/tree/${project.scm.tag}</url>
-    <tag>HEAD</tag>
+    <tag>maven-compiler-plugin-3.9.0</tag>
   </scm>
   <issueManagement>
     <system>JIRA</system>
@@ -77,7 +77,7 @@ under the License.
     <maven.it.failure.ignore>false</maven.it.failure.ignore>
     <surefire.version>2.22.2</surefire.version>
     <mavenPluginToolsVersion>3.6.2</mavenPluginToolsVersion>
-    <project.build.outputTimestamp>2020-04-07T21:04:00Z</project.build.outputTimestamp>
+    <project.build.outputTimestamp>2022-01-09T12:18:42Z</project.build.outputTimestamp>
   </properties>
 
   <contributors>
@@ -260,7 +260,7 @@ under the License.
           <artifactId>maven-javadoc-plugin</artifactId>
           <version>3.3.1</version>
           <configuration> <!--  remove after MPOM-269 -->
-            <tagletArtifacts combine.self="override"/>
+            <tagletArtifacts combine.self="override" />
           </configuration>
         </plugin>
       </plugins>